Properties: The most common in aq soln. Color light pink changing to yellow with increasing concn. Sharp absorption peak at 5027 Å. Americium dioxide, AmO2, is obtained by ignition of most trivalent Am compounds.

Derivative Type: Tetravalent americium

Properties: Known only in the solid state. When AmO2 or AmF3 is treated with fluoride, solid AmF4 results.

Derivative Type: Pentavalent and hexavalent americium compds

Properties: When obtained in soln are doubly oxygenated and have the general formula AmO2+n, where n = +1 for Am(V) and n = +2 for Am(VI). Hexavalent americium is yellow or light brown in dilute perchloric or nitric acid, green in fluoride solns and dark brown in sulfuric acid. A deep red ion complex is formed in bicarbonate-carbonate solns.

Use:241Am as radiation source for thickness gauging, density and radiographic measurements; parent for production of 242Cf and 242Pu; in ionization smoke detectors; for dissipation of static electrical charges. 241Am-Be mixture as neutron source. 243Am as target material for production of transcurium elements in high neutron-flux reactors.